Methods and products for transdermally administering particular chemicals are known in the art. Several U.S. patents have issued for the transdermal application of chemicals, most recently for nicotine. This invention expands the concept of transdermal delivery to cannabis, since the unique social and chemical characteristics of cannabis lend it to such an application.
Several medicinal uses have been found for the active ingredients of cannabis, including the ingredients tetrahydrocannabinol (THC), cannabinol (CBN), cannabidiol (CBD) and cannabichromene (CBC). The medicinal uses of cannabis include (1) treatment of nausea and pain associated with cancer and chemotherapy; (2) nausea, pain and wasting associated with AIDS; (3) arthritis and rheumatism; (4) glaucoma; (5) migraines; (6)muscle spasticity associated with multiple sclerosis and paralysis; (7) alcohol and narcotics withdrawal; (8) stress and depression; (9) asthma; and (10) epileptic seizures. Despite the many proven or suspected benefits of cannabis, legal and social barriers prevent its widespread use. Currently, only Marinol, a synthetic form of THC is available by prescription to patients. One purpose of the present invention is to extend the widespread medicinal use of cannabis without triggering the legal or social barriers associated with prescription of the drug.
The chemical composition of cannabis and its active ingredients allow for its transdermal delivery. For instance, the primary active ingredient of cannabis is THC, which is effective in vivo at very low doses. Due to its high liphophilicity, THC exhibits strong tendency to bind to tissue and protein, making transdermal application difficult. Fatal misuse has also been a concern in previous transdermal applications, but cannabinoids are rarely fatal when overdosed. Furthermore, THC is rapidly metabolized in the body, such that concentration levels of the chemical in the bloodstream decreases rapidly if administered through traditional methods. In contrast, a transdermal application allows for small dosages of THC to be administered over an extended period of time, thereby allowing the concentration levels of the chemical to remain relatively steady in the bloodstream.